From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mathieu Chouquet-Stringer Subject: Re: 2.4.19 kernel incorrectly reports # CPUs Date: 11 Sep 2002 11:56:18 -0400 Sender: linux-smp-owner@vger.kernel.org Message-ID: References: <6E5042539D21AF4E9C457B4DDCC3D6E10A9E6D@xch-nw-21.nw.nos.boeing.com> Mime-Version: 1.0 Return-path: In-Reply-To: <6E5042539D21AF4E9C457B4DDCC3D6E10A9E6D@xch-nw-21.nw.nos.boeing.com> List-Id: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "\"Watson, Randy E\"" Cc: linux-smp@vger.kernel.org randy.e.watson@boeing.com ("Watson, Randy E") writes: > I have built the 2.4.19 kernel for a dual processor Xeon system with a > SuperMicro P4DC6 mainboard.The kernel incorrectly finds four CPUs > instead of the two it has. Using "top" shows four active CPUs and cpuinfo > also shows four CPUs. I have built/run a number of other kernels (2.4.18, > 2.5.33) > recently on this system and they don't exhibit this problem. > > What may be causing this? Hi Randy, the cause of this is HT (HyperThreading) thus your dual Xeon (with HT enabled) looks like a quad CPU. This is expected behaviour... -- Mathieu Chouquet-Stringer E-Mail : mathieu@newview.com It is exactly because a man cannot do a thing that he is a proper judge of it. -- Oscar Wilde